The while loop when handling rw request may become deadloop in
case of bad card
I've seen mmcqd gets blocked forever after a single error message:
mmcblk0: error -110 sending read/write command, response 0x900, card
status 0x80e00
Also there was case of card reports status without error
mmcblk0: error -110 sending read/write command, response 0x900, card
status 0xe00
After this error, the card can stay in prg state, and never comes back,
and may not report any error further. So a break out condition
should be set in mmc block layer:
* should not enter the waiting loop in case of error
* should break out from the waiting loop, if card response with error
* should break out from the waiting loop when timeout
These will not help with the card, one more thing to do:
* re-init the card in case of too many errors
Signed-off-by: Ethan Du <[email protected]>
---
Changes since v1:
* Use mmc_reinit_host instead of mmc_detect_change
drivers/mmc/card/block.c | 36 ++++++++++++++++++++++++++++--------
drivers/mmc/core/core.c | 38 ++++++++++++++++++++++++++++++++++++++
include/linux/mmc/card.h | 3 +++
include/linux/mmc/host.h | 1 +
include/linux/mmc/mmc.h | 1 +
5 files changed, 71 insertions(+), 8 deletions(-)
diff --git a/drivers/mmc/card/block.c b/drivers/mmc/card/block.c
index d545f79..cc28a20 100644
--- a/drivers/mmc/card/block.c
+++ b/drivers/mmc/card/block.c
@@ -316,12 +316,14 @@ out:
return err ? 0 : 1;
}
+#define BUSY_TIMEOUT_MS (16 * 1024)
static int mmc_blk_issue_rw_rq(struct mmc_queue *mq, struct request *req)
{
struct mmc_blk_data *md = mq->data;
struct mmc_card *card = md->queue.card;
struct mmc_blk_request brq;
int ret = 1, disable_multi = 0;
+ unsigned long timeout = 0;
mmc_claim_host(card->host);
@@ -453,7 +455,9 @@ static int mmc_blk_issue_rw_rq(struct mmc_queue
*mq, struct request *req)
brq.stop.resp[0], status);
}
- if (!mmc_host_is_spi(card->host) && rq_data_dir(req) != READ) {
+ if (!mmc_host_is_spi(card->host) && rq_data_dir(req) != READ &&
+ !brq.cmd.error && !brq.data.error && !brq.stop.error) {
+ timeout = jiffies + msecs_to_jiffies(BUSY_TIMEOUT_MS);
do {
int err;
@@ -466,13 +470,22 @@ static int mmc_blk_issue_rw_rq(struct mmc_queue
*mq, struct request *req)
req->rq_disk->disk_name, err);
goto cmd_err;
}
+ if (cmd.resp[0] & R1_ERROR_MASK) {
+ printk(KERN_ERR "%s: card err %#x\n",
+ req->rq_disk->disk_name,
+ cmd.resp[0]);
+ goto cmd_err;
+ }
/*
* Some cards mishandle the status bits,
* so make sure to check both the busy
* indication and the card state.
*/
- } while (!(cmd.resp[0] & R1_READY_FOR_DATA) ||
- (R1_CURRENT_STATE(cmd.resp[0]) == 7));
+ if ((cmd.resp[0] & R1_READY_FOR_DATA) &&
+ (R1_CURRENT_STATE(cmd.resp[0]) != 7))
+ break;
+ } while (time_before(jiffies, timeout));
+ /* Ignore timeout out */
#if 0
if (cmd.resp[0] & ~0x00000900)
@@ -510,11 +523,11 @@ static int mmc_blk_issue_rw_rq(struct mmc_queue
*mq, struct request *req)
return 1;
- cmd_err:
- /*
- * If this is an SD card and we're writing, we can first
- * mark the known good sectors as ok.
- *
+cmd_err:
+ /*
+ * If this is an SD card and we're writing, we can first
+ * mark the known good sectors as ok.
+ *
* If the card is not SD, we can still ok written sectors
* as reported by the controller (which might be less than
* the real number of written sectors, but never more).
@@ -534,6 +547,13 @@ static int mmc_blk_issue_rw_rq(struct mmc_queue
*mq, struct request *req)
spin_unlock_irq(&md->lock);
}
+ card->err_count++;
+ if (card->err_count >= ERR_TRIGGER_REINIT) {
+ card->err_count = 0;
+ printk(KERN_WARNING "%s: re-init the card due to error\n",
+ md->disk->disk_name);
+ mmc_reinit_host(card->host);
+ }
mmc_release_host(card->host);
spin_lock_irq(&md->lock);
diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c
index 5db49b1..b61de33 100644
--- a/drivers/mmc/core/core.c
+++ b/drivers/mmc/core/core.c
@@ -1671,6 +1671,44 @@ int mmc_resume_host(struct mmc_host *host)
}
EXPORT_SYMBOL(mmc_resume_host);
+/**
+ * mmc_reinit_host - reinit a host
+ * @host: mmc host
+ */
+int mmc_reinit_host(struct mmc_host *host)
+{
+ int err = 0;
+
+ mmc_bus_get(host);
+
+ if (!host->bus_ops->resume)
+ return 0;
+
+ if (host->bus_ops && !host->bus_dead) {
+ if (!(host->pm_flags & MMC_PM_KEEP_POWER)) {
+ mmc_power_up(host);
+ mmc_select_voltage(host, host->ocr);
+ }
+ err = host->bus_ops->resume(host);
+ if (err) {
+ printk(KERN_WARNING "%s: error %d during resume "
+ "(card was removed?)\n",
+ mmc_hostname(host), err);
+ err = 0;
+ }
+ }
+ mmc_bus_put(host);
+
+ /*
+ * We add a slight delay here so that resume can progress
+ * in parallel.
+ */
+ mmc_detect_change(host, 1);
+
+ return err;
+}
+EXPORT_SYMBOL(mmc_reinit_host);
+
/* Do the card removal on suspend if card is assumed removeable
* Do that in pm notifier while userspace isn't yet frozen, so we will be able
to sync the card.
diff --git a/include/linux/mmc/card.h b/include/linux/mmc/card.h
index 6b75250..178de17 100644
--- a/include/linux/mmc/card.h
+++ b/include/linux/mmc/card.h
@@ -143,6 +143,9 @@ struct mmc_card {
const char **info; /* info strings */
struct sdio_func_tuple *tuples; /* unknown common tuples */
+ unsigned int err_count;
+#define ERR_TRIGGER_REINIT 1024
+
struct dentry *debugfs_root;
};
diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h
index 1575b52..cff9c69 100644
--- a/include/linux/mmc/host.h
+++ b/include/linux/mmc/host.h
@@ -235,6 +235,7 @@ static inline void *mmc_priv(struct mmc_host *host)
extern int mmc_suspend_host(struct mmc_host *);
extern int mmc_resume_host(struct mmc_host *);
+extern int mmc_reinit_host(struct mmc_host *);
extern void mmc_power_save_host(struct mmc_host *host);
extern void mmc_power_restore_host(struct mmc_host *host);
diff --git a/include/linux/mmc/mmc.h b/include/linux/mmc/mmc.h
index dd11ae5..3b979a1 100644
--- a/include/linux/mmc/mmc.h
+++ b/include/linux/mmc/mmc.h
@@ -122,6 +122,7 @@
#define R1_UNDERRUN (1 << 18) /* ex, c */
#define R1_OVERRUN (1 << 17) /* ex, c */
#define R1_CID_CSD_OVERWRITE (1 << 16) /* erx, c, CID/CSD overwrite */
+#define R1_ERROR_MASK 0xffff0000
#define R1_WP_ERASE_SKIP (1 << 15) /* sx, c */
#define R1_CARD_ECC_DISABLED (1 << 14) /* sx, a */
#define R1_ERASE_RESET (1 << 13) /* sr, c */
--
1.5.6.5
--
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